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Marine Places

Chesil Beach

Chesil Beach forms the seaward side of the Chesil Bank, a remarkably long, narrow bank of sedimentary material that connects the coast of Dorset in southern England to the Isle of Portland. Behind the bank is a tidal lagoon called the Fleet. Running parallel to the coast, Chesil Bank looks like a barrier island. However, because it connects the mainland to an island, it is classified as a tombolo. How Chesil Bank and its beach originally formed is debated—the most widely accepted theory is that it originally formed offshore and was then gradually moved to its current location by waves and tides. The beach is classified as a storm beach, as it is affected by strong waves because it faces southwest toward the Atlantic and the prevailing winds. Like most storm beaches, it is steep, with a gradient of up to 45 degrees, and is made of gravel.

Graded pebbles

Chesil Beach’s pebbles change in size progressively from potato-sized at one end to pea-sized at the other. This reveals the differences in wave energy along its length—at one end, strong waves wash smaller pebbles offshore; at the other, weaker waves wash them onshore.

Chesil Beachzoom image
  • Atlantic Ocean Northeast
  • Type Storm beach on tombolo
  • Composition Gravel of flint and chert
  • Length 18 miles (29 km)
  • Location West of Weymouth, Dorset, southern England
Chesil Beach habitat mapzoom image